Reasons Why
by somethingsdont
Summary: B/B. Post-100th. You know the drill.


**Title:** Reasons Why  
**Author:** Lucy (somethingsdont)  
**Pairing:** Booth/Brennan  
**Rating:** PG-13  
**Spoilers:** 5.16, The Parts in the Sum of the Whole  


* * *

Her head against his shoulder felt like an apology that she didn't immediately know how to verbalize. Booth wanted, so much, to reassure her that it was okay, that nothing would change between them, but somewhere between his aching heart and his burning lips, the words faded away. Words better left unspoken, he knew, because the conviction behind them would be questionable at best.

He should've known that gambles were often cruel and ruthless. He should've known better than anyone.

No risk, no reward. Wasn't that the mantra?

But this was not a couple benjamins he tossed into a match of pool. He was damn good at pool. He'd always thought he was good at this, too, whatever this was, but she defied all his rules, broke them, leaving him desperate and craving answers. And her. He couldn't stop craving her.

She was his partner, an ally in a world of adversaries, and easily the woman he held closest to his heart. Despite knowing that it was too late to do things differently, and that the outcome would remain unchanged, he couldn't help but question his timing, his delivery, every moment leading up to _this_ very moment, where he stood dejected and utterly heartbroken, shouldering more than just the physical weight of her cranium.

Cranium. It was such a Bones word that he nearly laughed, if only to dissipate some of the energy he carried in his chest. He heard her in his head, explaining to him that the cranium was the part of the skull that excluded the mandible, and thus not the term he had meant to use. _A common misconception, Booth._

"Booth, please don't cry." Brennan's words were a mere whisper, her warm breath lightly ghosting his chin as he turned to look at her.

"I'm not," he replied out of reflex. "I—I'm not crying."

Brennan slowed her pace to a stop, and Booth slowed with her. Tenderly, she turned to face him.

"Booth… I'm sorry."

He shook his head. "Bones, don't do that."

She lifted her fingertips to his cheek, and neither said anything as she wiped at the tears staining his skin. Her eyes were piercing blue in the dark, mesmerizing still, and he felt drawn to her, now more so than ever before. He found comfort in her, despite her rejection being the source of his heartache. This 'moving on' thing would be an uphill battle, he knew.

He cleared his throat. "Do you, uh, do you need a ride home?"

A flash of alarm appeared in her eyes, and it stung to realize this was the way she reacted to him now. "I'll take a cab," she replied evenly. "Booth, I—"

He found himself hanging on to every last word, waiting for any indication that she was reconsidering. But her demeanor suddenly shifted mid-sentence, and she never spoke the rest.

"I'll see you tomorrow, Booth."

Her fingers brushed his jaw as she stepped away.

*

The Jeffersonian loomed ahead against the backdrop of dark skies. Brennan's cab pulled up to the building, and after paying the driver, she stepped outside. The air was fresh, chilled by the winds that gently gusted, and Brennan felt herself being soothed by the proximity of her workplace. She felt the compulsion to occupy her time with tasks she excelled at instead of those where she felt lacking.

But her lips were hypersensitive, still, and her heart seemed to periodically press painfully against her ribcage, though she understood the improbability of her developing cardiomegaly as a result of Booth's confessions.

At the mention of his name, even only in her thoughts, her chest clenched tightly and for a moment, it hurt to even breathe. But she inhaled against the temporary pain and walked toward the closest thing she had to comfort.

Brennan slipped into the building and headed for her office. The lab was quiet, dark except for a small glimmer of light gleaming from what appeared to be Angela's office. Hoping whoever was there wouldn't notice her entry, Brennan walked quietly in the darkness, knowing the layout of the lab so well that she had no trouble navigating to her destination.

She flicked on the lights in her office and settled down at her desk. She felt the immediate itch to write. Not about how she felt, though she was running on a myriad of unwelcome emotions, but about what she knew. She wanted to pen facts and numbers. There was something so reassuring about a fact supported by evidence. There was logic and knowledge and science. One and one always summed to two. But adding a man to a woman amplified the complexity of the problem, blurring the variables, and she wanted so badly to be able to model interpersonal relationships and run simulations on them.

The larger the sample, the smaller the margin of error. She saw in humans a craving for companionship, for community. It was instinctual and evolutionary and anthropological. It made sense. Booth's anecdote about the elderly did not. Not to her.

"Brennan, hey."

Brennan looked up and saw Angela standing in the doorway, a sketchbook cradled against her chest.

"Angela, what are you doing here so late?"

Angela motioned toward her sketchbook. "Had a few reconstructions to catch up on." She stepped into Brennan's office and approached her desk. "What about you? Didn't you have that meeting with Sweets today?"

Brennan nodded, a sense of dread creeping into her system.

"Well, how'd that go?" Angela asked. Her tone was cautious, Brennan noticed, and she wondered if Angela already knew the things that she did not. She'd always admired that fierce compassion in the artist, and their time together had filled her with knowledge she couldn't extract from textbooks.

"Booth told me that he is a gambler."

Angela appeared confused. "But you knew that already."

"No, Angela," Brennan explained, shaking her head. She felt it again, deep in her chest. "He was not sharing a detail of his past. He used that fact as a preface to a proposal that we enter into a romantic relationship."

"Wait, _what_?" Angela's eyes grew large as she processed Brennan's words. Angela leaned in, her hands falling to Brennan's desk in support, and her sketchbook slapped loudly against the surface. "Oh my god, Bren. Oh my _god_. _Brennan_."

"No, I—" Brennan swallowed hard. "I rejected him."

Angela's delirium was immediately replaced with horror. "What? _Why_?"

"Because, Ange," Brennan replied quietly, repeating her words from earlier in the night. "I don't know how."

Angela began pacing the room, her sketchbook waving wildly in the air. "No, no, _stop_. Are you listening to yourself? Rewind." She stopped abruptly and turned to Brennan, her features filled with incomprehension. "Booth asked you out."

"More accurately, he talked about the intuition of older couples, and—" She trailed off, and the dull ache in her chest became piercing. An air of desperation slid into her voice. "He says that he _knew_, Ange, right from the beginning." She heard him clearly in her mind, speaking those words. _I'm that guy. Bones, I'm that guy. I know._ Her eyes began to water again, but she tightened her resolve, unwilling to cry. She looked up at her best friend, hurting and pleading for validation. "That's not legitimate evidence, Angela. I can't accept that argument. I don't—" She held back a sob, feeling the weight of the past hour crashing down on her, and knowing that it could only be worse for Booth.

Angela's demeanor softened, and she neared the desk again. Quietly, she pulled Brennan out of her chair and into a tight embrace. "You're going to be okay, sweetie," she soothed over her shoulder. "The two of you will figure this out."

After that, they did not talk about Booth, or what he told her and how Brennan responded. Angela drove Brennan home and stayed up with her until the early hours of the next morning, sipping wine and exchanging ideas. New ideas, old ones, and Brennan wrote them down in a bulleted list, focusing on the tangible. On what she knew. Angela sketched Brennan's list, breathing life and beauty and tragedy into cold, detached statements.

Around four in the morning, Angela dozed off, her sketchbook opened to an unfinished drawing of an item halfway down Brennan's list: _the heart fuels the brain_. In parentheses, Brennan had added _by sending blood through the carotid artery_, but Angela's interpretation had produced a knight crouched on the ground, attempting to hold together a fractured skeletal structure.

*

It was the first day of work that Brennan had missed in three years, and the first ever without a clearly-defined, extensively corroborated reason. Cam had seemed suspicious, but she didn't pry. It was early still, and Angela was sprawled across the couch, asleep and half-covered by a blanket Brennan had brought her.

Just as Brennan was about to return to sleep herself, her phone rang. It was Booth.

"Bones, we've got a case."

His voice was familiar but carried with it a different edge, one of caution, and uncertainty, and sorrow. Her heart felt tender, suddenly, and she wanted so much to reach through the phone and touch him, if only to reassure herself of his vigor. And because, she knew, without the contact, her next words would act as a tough blow, however unintentional.

"I'm not coming in today, Booth. I just informed Cam." There was a long pause at the other end, and she rushed to explain. "Not because of—us. Angela and I had a bit of a late night."

"Okay." Another pause, more stifling. "See you tomorrow, Bones."

When they hung up, Brennan did not get back to bed, opting instead for a large mug of coffee to sustain her. Thoughts ran rampant in her head, and the more she tried to organize them, the more haphazard they became. It rushed back to her all at once, the feeling of standing in front of a man, ever courageous, as he poured his heart out – figuratively, of course. She'd experienced exhilaration and panic and fear. She felt them now. Fight or flight.

She picked up her phone and quickly hit Booth on speed dial. She barely waited for him to answer before speaking.

"This isn't who we are, Booth. This isn't." She heard the desperation in her own voice, the insistence, and she felt young, powerless as though she was witnessing her own life from behind a glass wall.

"Bones," came the reply. Booth sighed, almost in defeat. "You tell me who we are, because I don't think I know anymore."

"Yes, you do. You're the one who's always known, Booth," she insisted, unaware of her own phrasing.

There was a brief pause, and his voice filled with venom. "Did you call just to throw my words back at me?"

His silent rage shook her, and it _hurt_. "No, I didn't mean—"

"I know," Booth interrupted, softening. "I'm sorry. I just need some time with this." He hesitated. "We're going to be okay, Bones." He sounded entirely unconvincing, but she held on to his words, storing them as a promise. She heard him shifting his phone against his ear. "Listen, Bones. I gotta go."

They exchanged strained goodbyes and hung up.

"Everything okay, Bren?"

Angela padded to the kitchen with the blanket draped over her shoulders. Her hair was messy from sleep, and she poured herself a cup of coffee, then slipped into the stool next to Brennan.

"I'm going to lose him, Ange," she said softly as the realization dawned on her.

"You won't," Angela replied, taking a long drink of coffee.

Brennan turned to face her. "You can't know that. You have nothing to support your claim."

"Neither do you," Angela countered. "Brennan, listen to me. Booth loves you, whether you want to acknowledge that or not. He's just devastated right now, and he needs time to figure this out for himself. If you're truly going down this path, let him have that time. Let him heal."

Brennan tightened her grip around her coffee mug. "I would do anything for him."

"Except give him a chance," Angela replied pointedly.

Brennan shook her head vehemently. "No, Angela, it's not about a chance. It's about my inability to be the person Booth needs."

"Booth needs _you_, sweetie."

"He needs someone who will love him thirty, forty, fifty years from now. He said it himself. I can't make that promise. I can't be that person." She turned to Angela, tears prickling against her eyelids. "Nobody can know how they'll feel in thirty, forty, fifty years. Nobody."

"Then love him today," Angela said simply. "Love him today, and when you wake up tomorrow morning, love him tomorrow. Love him one day at a time, one week at a time. That's all he really wants, Bren. That's all any of us really want."

"And if, ten years from now, I wake up and I don't love him anymore?" Brennan asked against the lump forming in her throat.

Angela smiled sadly. "Then he'll let you go. And you'll both move on knowing that you loved each other for ten years." She paused. "Do you think I regret Jack?"

"I have no way of knowing."

"I don't," Angela replied. "Not for a moment. I know you, Brennan. I know that you can't subscribe to eternity, even if you've come to accept the merits of love, but Booth doesn't want a promise of forever. He just wants you, for as long as you want him back."

"How do you know that?" Brennan asked in disbelief, wary of how simple it sounded. "How can you be sure?"

"Because of the way he looks at you. Because he's Booth."

Brennan sipped at her coffee. "Those are—"

"Unscientific and immeasurable," Angela interrupted. "I know. But Brennan, whatever you've rationalized in that brilliant head of yours is flawed. You're running on fear."

"No, Ange, what do I possibly have to be afraid of?"

"His belief in you," Angela explained gently. "This irrational, insane, completely crazy thing you feel for each other."

Brennan looked down at her mug, now nearly empty. "You know what I think about psychology, Angela."

Angela paused expressively, sipping neatly at her coffee before speaking. "Forget psychology, Bren. This is _Booth_."

Those words elicited a single teardrop from Brennan, and it felt like relief. This was _Booth_. Booth, with his kind eyes and gentle heart. Booth, with his fierce loyalty and untainted sense of justice. Booth, who was willing, so many times, to put his life and career in jeopardy for her, because he believed in her, cared for her, and fell in love with her. And she understood then what he'd known all along.

Angela wrapped an arm around Brennan's shoulder, pulling her close.

"I hurt him."

Angela nodded. "I know, sweetie, he'll forgive you. Give yourself a chance."

Angela held Brennan as she silently cried, not for what she had almost lost but for what she had finally found.

*

The night was quiet and unusually warm; after an exceptionally cold and blizzard-filled winter, the mild weather was a welcome change. Booth found himself outside the empty courthouse, staring up at the building without purpose. Something had drawn him here, a gut feeling, and he followed that bout of subconscious all the way to an abandoned bench that he remembered well. He collapsed onto it, exhausted. He sat there, lost in his own thoughts, until the clicking of familiar heels pulled him from his reverie.

Ten feet away, Brennan stood, seemingly unsure, but with a hint of sheer determination etched across her features. Booth felt his pulse hammering at the sight of her.

"Bones."

She smiled as she approached him.

Booth stood up, fighting the wave of emotion her presence elicited. "What are you doing here?"

She looked down at his shoulder, then back up. "You weren't at home, in your office, or at the diner."

He chuckled dryly, strangely. "You didn't really go to all those places." When she didn't say anything, he sobered. "Why didn't you just call?"

"I did," she replied. "Went to voicemail."

"Oh, I—" He fumbled around in his pockets. He squinted at the screen when he pulled out his phone. "Had it on silent. Sorry, Bones."

"I spoke to Angela," she told him.

He shoved his phone back into his pocket, keeping his eyes trained on hers. "What'd she say?"

"She… provided me with insight, and pointed out the flaws in my assumptions."

"Your assumptions?"

Brennan took a deep breath. "There is no way to know how I will feel in thirty years. I don't even know that I'll be alive in thirty years."

Booth lifted his hand to stop her. "Don't say that, Bones."

"It's true," she argued methodically. "Nobody has the ability to predict the future. But—" She trailed off, and something shifted in her features. Her irises darkened. "But I know something about today."

He watched her with caution, waiting patiently with an aching heart and a desire to protect her from the fright he saw in her. "What do you know?"

"That I love you, Booth," she said in a whisper, her eyes shining with unshed tears. "Today, in this instant, I know, and it is a fact."

Booth stumbled, his mind clearing of all thought. "Bones, I—"

She slid her hand against his cheek, silencing him. "I am not a gambler. I am a scientist," she continued, recalling her words from the previous night. "But science is not the only source of my knowledge, and if there's one thing you've taught me, that's it. I am not a gambler, Booth, but I want a chance. I can't promise you my life, not because I think I won't still love you thirty years from now, or forty, or fifty, but because I don't know _how_ to make that promise." Tears ran freely down her cheeks, and she swiped uselessly at them with her fingertips. "This is everything I have, and if it's insufficient—"

"Bones."

He kissed her, pouring into her everything he had wanted to verbalize, and she eased against his lips, unafraid. The weight in his chest lifted, and he felt all his senses tuning in to her movements. Her wind-chilled tears were cool against his cheek. She did not hesitate, did not push him away, and he kissed her thoroughly as his own tears mingled with hers. Tears of relief, and pent-up anxiety, and unadulterated joy.

She touched his cheek as they pulled apart, the pad of her thumb soaking up the moisture on his skin. She leaned in and pressed a kiss to the corner of his mouth, briefly.

"Thank you," she said quietly, "for never giving up."


End file.
